Orthodontic implant

ABSTRACT

The invention relates to an implant with fastening means ( 2 ) to be fixed to the bone of a person&#39;s upper jaw ( 5 ) or lower jaw ( 30 ), comprising a mounting element ( 3 ) for mounting orthodontic appliances, whereby said mounting element ( 3 ) is connected to said fastening means ( 2 ) by means of a connecting piece ( 4 ) which must extend through the gum surrounding the corresponding bone, whereby the mounting element ( 3 ) has at least one recess ( 17 ) in which a corresponding mounting element ( 14 ) of said appliances must be mounted.

[0001] The present invention concerns an orthodontic implant which makesit possible to gradually move a person's teeth showing an incorrectimplantation into an adjusted position by exerting an almost continuouspressure force or tensile force on these teeth.

[0002] The means used according to the present state of the art for thusadjusting the position of a person's teeth comprise different sorts ofbraces which can be placed in an either or not removable manner in aperson's mouth. For some persons, what is called an outer brace ismoreover required, which exerts an additional force on the person'steeth or on the upper or lower jaw, for example via the neck.

[0003] Such braces are particularly unpleasant to wear and they do notalways make it possible to obtain a precise, reproducible distributionof power on the person's teeth or jaw.

[0004] The invention aims to remedy these disadvantages by proposing anorthodontic implant which makes it possible to change the position of aperson's teeth in a simple and precise manner. When using an implantaccording to the invention, the use of an outer brace is no longerrequired, and remarkably good results are obtained.

[0005] To this aim, the orthodontic implant according to the inventionhas fastening means to be fixed to the bone of a person's upper jaw orlower jaw, and it further comprises a mounting element for mountingorthodontic appliances, whereby said mounting element is connected tothe above-mentioned fastening means by means of a connecting piece whichmust extend through the gum surrounding the corresponding bone.

[0006] Practically, said mounting element contains at least one borehole which is provided with thread co-operating with a bolt which makesit possible to fix said appliances to the implant.

[0007] According to a preferred embodiment of the implant according tothe invention, said mounting element has at least one recess in which acorresponding coupling element of said appliances is to be mounted.

[0008] According to a special embodiment of the implant according to theinvention, said connecting piece is bent in order to make sure that thelongitudinal axis of said recess extends almost parallel to the lateralsurfaces of the teeth situated in the jaw upon which said implant mustbe fixed.

[0009] According to an advantageous embodiment of the implant accordingto the invention, said fastening means are formed of a plate which isprovided with one or several recesses through which screws fit forfixing the implant to the bone of said upper or lower jaw.

[0010] In an advantageous manner, the above-mentioned mounting elementis at least partially spherical.

[0011] According to an interesting embodiment of the implant accordingto the invention, the above-mentioned connecting piece has a crosssection with round angles, or a circular or elliptic cross section.

[0012] Other particularities and advantages of the invention will becomeclear from the following description of a few specific embodiments ofthe implant according to the invention; this description is given as anexample only and does not restrict the scope of the claimed protectionin any way, the reference figures used hereafter refer to theaccompanying drawings.

[0013]FIG. 1 is a schematic view in perspective of the implant accordingto the invention.

[0014]FIG. 2 is a schematic side view of a skull where the implantaccording to the invention is fixed to the upper jaw.

[0015]FIG. 3 is a schematic bottom view of an upper jaw onto which theimplant according to the invention is attached.

[0016]FIG. 4 is a schematic side view of a skull where the implantaccording to the invention is fixed to the lower jaw.

[0017]FIG. 5 is a schematic side view of part of an upper jaw providedwith the implant according to the invention, with orthodonticappliances.

[0018]FIG. 6 is a schematic side view of part of an upper jaw providedwith the implant according to the invention, with different orthodonticappliances.

[0019]FIG. 7 is a schematic side view of part of a lower jaw which isprovided with an orthodontic implant according to the invention.

[0020]FIG. 8 is a schematic side view of an implant according to aninteresting embodiment of the invention.

[0021]FIG. 9 is a schematic front view of the implant from FIG. 8.

[0022]FIG. 10 is a schematic side view of an implant according toanother embodiment of the invention.

[0023]FIG. 11 is a schematic front view of the implant from FIG. 10.

[0024] In the different drawings, the same reference figures refer toidentical or analogous elements.

[0025] The invention in general concerns an orthodontic implant whichmakes it possible to connect orthodontic appliances, such as for examplefixed braces, to the bone of a person's upper or lower jaw.

[0026] Fixed braces are known as such. With such braces, what are calledbrackets are fixed to the teeth. These brackets are mutually connectedvia a metal wire which makes it possible to exert an almost continuousforce on the brackets so as to move certain teeth gradually into anadjusted position.

[0027] The implant according to the invention is connected to this wire,or to one or several brackets, via a coupling element so as to exert asuitable force in order to adjust the position of the correspondingteeth.

[0028]FIG. 1 represents a specific embodiment of an orthodontic implantaccording to the invention. This implant 1 has fastening means 2 to befixed to the bone of an upper or lower jaw and a mounting element 3 forconnecting orthodontic appliances to the implant 1.

[0029] The fastening means 2 and the mounting element 3 are connected toone another via a connecting piece in the shape of a rod 4 with acircular cross section.

[0030] This implant 1 is fixed to the bone of a person's upper jaw 5 bymeans of the above-mentioned fastening means 2, as is represented inFIGS. 2 and 3.

[0031] Thus, the fastening means 2 have a T-shaped osteosynthesis platewith four circular recesses 6, 7, 8 and 9. Through these recesses fitcorresponding screws 10, 11, 12 and 13 for fixing the fastening means 2tight to the bone of the jaw 5.

[0032] As is clearly represented in FIG. 3, the fastening means 2 makeit possible to fix the implant 1 to the lower side of the boneconnecting the upper jaw 5 to what is called the zygoma. To this end,said osteosynthesis plate is preferably slightly bent.

[0033] Said rod 4, forming the connecting piece between the fasteningmeans 2 and the mounting element 3, extends through the gum surroundingthe jawbone 5, such that the mounting element 3 is situated in the oralcavity between the jawbone and the cheek. For clarity's sake, the gum isnot represented in the figures.

[0034] In order to obtain a tight connection between the rod 4 and thegum, and in order to make sure that the latter does not get irritated bythe rod 4, it has a cross section with round edges, and this section ispreferably circular. According to an advantageous embodiment, the rod 4has a smaller diameter than the mounting element 3.

[0035] In an advantageous manner, the mounting element 3 is madespherical or drop-shaped at least on the side of the rod 4. As this hasfor a result that there are no sharp edges which could get into contactwith the lips, the cheeks or the gum, the formation of wounds therein isavoided. Preferably, however, the entire mounting element 3 is madespherical or drop-shaped.

[0036] Via this mounting element 3, said orthodontic appliances arefixed to the implant. FIG. 5 thus schematically represents an implant 1which is connected via a coupling element, in particular a tie-bar 14,to a fixed brace containing a number of brackets 15 which are each fixedto a tooth 20 and which are connected to a metal wire 16 in a mannerknown as such.

[0037] The tie-bar 14 is fixed to the mounting element 3 of the implant1 via one end. To this end, the mounting element 3 has a longitudinal,preferably cylindrical recess 17 in which said far end of the tie-bar 14fits.

[0038] In order to fix the tie-bar 14 tight to the mounting element 3,the latter is provided with a cylindrical bore hole 18 in which isprovided a thread co-operating with a bolt 22. The axis 19 of the borehole 18 extends almost perpendicular to the axis 21 of the recess 17 andintersects the latter, such that, by means of said bolt 22, the tie-bar14 can be clamped in said recess 17.

[0039] In order to make sure that the tie-bar 14 cannot rotate inrelation to its axis, it will preferably have a cross section in theshape of a right-angled quadrangle. Thus, the bolt 22 pushes with itsflat end against a lateral surface of the tie-bar 14 which is mounted inthe cylindrical recess 17, and it is thus clamped tight in the latter.

[0040] According to an advantageous embodiment of the implant accordingto the invention, said rod 4 is bent, so that the axis 21 of said recess17 extends almost parallel to the lateral surfaces of the teeth 20situated in the jaw upon which the implant 1 is fixed.

[0041] Thus, the axis 21 of this recess 17 extends for example at anangle between some 60° and 150° in relation to the fastening means 2.

[0042] According to a preferred embodiment of the implant according tothe invention, said tie-bar 14 has an eye at its far end which is to befixed in said recess 17, such that the bolt 22 situated in the bore hole18 extends through this eye, as a result of which the tie-bar 14 isfixed tight to the mounting element 3.

[0043] The cross section of the tie-bar 14, as well as that of therecess 17, can have all sorts of shapes and can for example be circularor hexagonal.

[0044] The free end of the tie-bar 14 has a hook 23 through which saidmetal wire 16 extends. The hook 23 presses against a round disc 24 whichis coaxial to said wire 16 and which can move according to thelongitudinal direction of the latter.

[0045] Further, a spiral compression spring 25 is provided which iscoaxial to said metal wire 16 as well, and which pushes against saiddisc 24 on the one hand, and against a tubular element 26 of a bracket15 on the other hand. In this manner, an almost continuous pressureforce is exerted via the implant 1 on the corresponding tooth 20, towhich the concerned bracket is attached.

[0046]FIG. 6 represents another application of the implant according tothe invention, whereby a tensile force is exerted on a tooth 20. Atie-bar 14 is hereby fixed in said recess 17 of the mounting element 3.On the free end 27 of this tie-bar 14 is attached a spiral draw spring28 which is connected to a tension member 29 co-operating with a bracket15 which is fixed to a tooth 20. Thus, via the implant 1 is exerted atensile force on this tooth 20 which makes sure that the position of thelatter is gradually adjusted.

[0047] According to a variant of this embodiment, the spiral spring 28can for example be connected directly to the mounting element 3, and theuse of a tie-bar is not required.

[0048] Possibly, the spiral spring 28 can be replaced by another elementexerting a tensile force, such as for example a rubber band.

[0049] Naturally, the implant according to the invention is preferablymade of a bio-compatible material, such as for example titanium.

[0050] In the accompanying figures, the orthodontic implant 1 isattached to the jaw near a person's rear molars. However, it is alsopossible to fix it to other places on the jaw bone. To this end, theshape of said osteosynthesis plate will possibly have to be adjusted tothe bone concerned, and it may be necessary to change the length andshape of the above-mentioned connecting piece correspondingly.

[0051]FIG. 4 is a schematic representation of the orthodontic implantaccording to the invention when fixed to the lower jaw. In this case,the shape of said osteosynthesis plate is adjusted such that it can beconnected to the bone of the lower jaw where it is to be mounted.

[0052]FIG. 7 is a schematic side view of a lower jaw 30 whereby theorthodontic implant according to the invention is attached to the jawbone in order to raise a molar 31 from the represented toppled position.This implant has fastening means 2 in the shape of an osteosynthesisplate with three recesses through which a screw 10, 11 and 12 extendseach time in order to fix the implant 1 to the lower jaw 30. Further, aconnecting rod 4 extends up to a spherical mounting element 3. Thelatter is represented as a cross section and has a bore hole 18 openinginto a cylindrical recess 17 which extends almost crosswise to said borehole 18. Thus, a coupling element can be fixed in the recess 17 via abolt 22 provided in the bore hole. This coupling element consists of atie-bar 14 and is mounted in said recess 17 with one far end, whereasthe other far end is equipped with a spiral spring 32.

[0053] The central axis of the recess of the mounting element 3preferably extends almost parallel to the fastening means 2 and to thelateral surfaces of the teeth 20 of the lower jaw 30.

[0054] The tie-bar 14 has a flat side on the far end situated in therecess 17, whereby the bolt 22 pushes against this side, such that thetie-bar 14 is fixed in the mounting element 3. On the far end situatedin the recess 17, the tie-bar 14 preferably has four flat sides, and,consequently, it has a quadrangular cross section allowing us to fix itin different positions in the mounting element 14.

[0055] The spiral spring 32 is further connected to a relatively rigidwire 16 co-operating with the latter via a bracket 15 which is attachedto the molar 31 to be raised. Thus, the spiral spring 32 exerts analmost continuous pressure force on the molar 31, and it is graduallyraised in relation to the lower jaw 30.

[0056]FIGS. 8 and 9 schematically represent a very interestingembodiment of the implant according to the invention. This embodimentdiffers among others from the above-described embodiments in that themounting element 3 is cylindrical, whereby it is coaxial to the rod 4which is bent over an angle of for example 90°.

[0057] This mounting element 3 has two cylindrical recesses 17 and 33which extend crosswise to the longitudinal axis 34 thereof, and whichare almost perpendicular in relation to one another. Further, themounting element 3 is provided with a threaded bore hole 18 which iscoaxial to the mounting element 3, and which extends between saidrecesses 17 and 33 and the lateral surface 35 of the mounting element 3situated opposite to said rod 4. Thus, it is possible to fix orthodonticappliances, such as a tie-bar, in one of the recesses 17 or 33 by meansof a bolt which is screwed in the bore hole 18.

[0058] Such a mounting element 3 makes it possible, among others, to fixorthodontic appliances in different directions, depending on the usedrecess 17 or 33. Moreover, this mounting element 3 offers a majoradvantage in that said bore hole 18 extends substantially cross-wise tothe lateral surfaces of the teeth, after the implant has been fixed to ajaw, such that this bore hole 18 is easily accessible in the oral cavityfor screwing a bolt in it.

[0059] Further, the implant according to this embodiment of theinvention has fastening means 2 in the shape of an osteosynthesis platewith three circular recesses 6, 7 and 8 for fixing the implant to aperson's upper or lower jaw by means of corresponding screws.

[0060] In an advantageous manner, the fastening means 2 are made of aresorbent material, in particular such as for example a resorbentpolymer containing L-lactide, D-lactide and Glycolide in a molecularratio of 85/5/10, whereas the mounting element 3 and the rod 4 are madefor example of titanium.

[0061] This rod 4 is then connected to the fastening means 2 by means ofa screwed joint, for example. After the teeth have been put into anadjusted position, the rod 4 with the mounting element 3 is detachedfrom the fastening means 2, for example by loosening the rod 4, and itis thus removed. It is not required then, to remove the fastening means2, since they have been entirely resorbed after for example one to twoyears.

[0062] In a very advantageous manner, apart from the fastening means 2,also the mounting element 3 and the rod 4 are made of a resorbentmaterial.

[0063] In a manner which is also very advantageous, the fastening means2, the mounting element 3 and the rod 4 are made in one piece, and theyare made for example of a resorbent material. After the teeth have beenput into an adjusted position, the rod 4 with the mounting element 3 isdetached from the fastening means 2, for example by breaking off the rod4 or by cutting it through, and it is thus removed.

[0064] The embodiment of the implant according to the invention, as isrepresented in FIGS. 10 and 11, differs from the preceding embodiment inthat the rod 4 is not bent. This rod 4 is made such that it can be bentin the required position by heating it, for example. Further, thecircular recesses 6, 7 and 8, which are provided in the osteosynthesisplate 2, extend according to the longitudinal axis of the rod 4 whichcoincides with the rod 34 of the mounting element 3.

[0065] It is clear that, according to the invention, the embodiment ofthe implant as represented in FIGS. 8 and 9, can also be made with a rod4 which is not bent, such as in the embodiment of the implant asrepresented in FIGS. 10 and 11.

[0066] It is also clear that, in order to avoid wounds being formed inthe oral cavity, the mounting element 3 has round angles.

[0067] The placing of the implant according to the invention on thelower or upper jaw only requires a small surgical treatment. A smallincision is made in the gum under local anaesthesia on the spot wherethe implant has to extend through the gum. Next, the fastening means 2are fixed to the underlying jaw bone, and the gum around the connectingelement is sutured, such that the mounting element 3 protrudes in theoral cavity. The orthodontic appliances are preferably only connected tothis mounting element 3 after the gum has healed and the screws withwhich the implant has been fixed have sufficiently knitted together withthe bone.

[0068] The invention is by no means restricted to the above-describedembodiments of the orthodontic implant according to the inventionrepresented in the accompanying drawings. On the contrary, severalvariants are possible within the scope of the present invention, as faras the dimensions and shapes of the implant are concerned as well as theorthodontic appliances attached to it.

[0069] For example, these orthodontic appliances are not restricted tothe brackets 15, the metal wire 16, the tension member 29 and the spiralsprings 25, 28 and 32 described above, but they also comprise all theother usual orthodontic elements which can be placed in the oral cavityin order to adjust the position of certain teeth.

[0070] Moreover, the implant cannot only be connected to a brace withbrackets, it can also work in conjunction with any type of braces.

[0071] Although a mounting element 3 has been described having a recess17 working in conjunction with a bolt 22 for fixing a tie-bar 14 orother orthodontic appliances, several variants are possible. Thus, thetie-bar 14 can for example be fixed to the mounting element by means ofgluing or via a clamped joint.

[0072] It is also possible for the mounting element 3 to be mounteddirectly to the metal wire 16, or to other orthodontic appliances, inorder to avoid the use of a tie-bar 14.

[0073] In certain cases, it may be interesting to provide severalrecesses 17 in one and the same mounting element 3, such that severalcoupling rods 14 can be fixed to one and the same implant 1.

[0074] Further, the shape of the fastening means 2 is not restricted, ofcourse, to an osteosynthesis plate with four recesses, but it can haveall sorts of shapes, and possibly more or less recesses andcorresponding screws. Thus, the fastening means 2 can for example beformed of a small threaded rod which is screwed directly in the jawbone.

1. Implant with fastening means (2) to be fixed to the bone of aperson's upper jaw (5) or lower jaw (30), comprising a mounting element(3) for mounting orthodontic appliances, whereby said mounting element(3) is connected to said fastening means (2) by means of a connectingpiece (4) which must extend through the gum surrounding thecorresponding bone, and whereby the mounting element (3) has at leastone recess (17) in which a corresponding mounting piece (14) of saidappliances must be mounted, characterised in that the mounting element(3) showing no sharp edges has a recess (17) and is provided with athreaded bore hole (18) cooperating with a bolt (22), whereby the axis(19) of the bore hole (18) intersects the axis (21) of said recess (17)at right angle such as to fix said appliances (14) to the implant insaid recess (17) by means of said bolt (22) which is screwed in the borehole (18), whereby said fastening means (2) ate formed of a plate whichis provided with one or several recesses (6,7,8,9) through which fitscrews (10,11,12,13) for fixing the implant to the bone of said upper orlower jaw.
 2. Implant according to claim 1, characterised in that saidmounting element (3) is at least partially cylindrical, whereby thismounting clement (3) is coaxial to said bore hole (18) and to saidconnecting piece (4).
 3. Implant according to claim 1, characterised inthat said connecting piece is formed of a rod (4).
 4. Implant accordingto claim 2, characterised in that said rod (4) has a circular section.5. Implant according to any of claims 1 to 4, characterised in that saidmounting element (3) is at least partially spherical.
 6. Implantaccording to any of claims 1 to 5, characterised in that said mountingelement (3) is drop-shaped.
 7. Implant according to any of claims 1 to6, characterised in that said recess (17) is mainly cylindrical. 8.Implant according to any of claims 1 to 7, characterised in that saidbore hole is coaxial to said connecting piece (4).
 9. Implant accordingto any of claims 1 to 8, characterised in that said connecting piece (4)is bent in order to make sure that the longitudinal axis (21) of saidrecess (17) extends almost parallel to the lateral surfaces of the teeth(20) situated in the jaw (5,30) to which said implant must be fixed. 10.Implant according to any of claims 1 to 9, characterised in that thelongitudinal axis (21) of said recess (17) extends at an angle betweensome 60° and 150° in relation to said fastening means (2).
 11. Implantaccording to any of claims 1 to 10, characterised in that thelongitudinal axis (21) of said recess (17) extends almost parallel tosaid fastening means (2).
 12. Implant according to any of claims 1 to11, characterised in that said fastening means (2) are formed of a platewhich is provided with one or several recesses (6,7,8,9) through whichfit screws (10,11,12,13) for fixing the implant to the bone of saidupper or lower jaw.
 13. Implant according to any of the precedingclaims, characterised in that it is made of titanium.